Add special cases for read(size <= 0)

A read of 0 isn't particularly useful, but it is weird that it will
cause a BrokenPipeError. Instead, it makes more sense to just return an
empty string.

A read of <0 would normally read until EOF, but we already have that
feature in readall() and it wouldn't be particularly useful here.  A
similar functionality of reading the entire current contents of the
buffer is useful, though.  This is already implemented in
readall_nonblock() and this would be a nice user-facing way of calling
that.

Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

1 files changed, 9 insertions, 4 deletions

diff --git a/sploit/comm.py b/sploit/comm.py
index e9ea53d..8078c9f 100644
--- a/sploit/comm.py
+++ b/sploit/comm.py
@@ -24,10 +24,15 @@ class Comm:
         except BrokenPipeError:
             pass
 
-    def read(self, size):
-        data = self.back.stdin.read(size)
-        if(data == b''):
-            raise BrokenPipeError('Tried to read on broken pipe')
+    def read(self, size=-1):
+        if size < 0:
+            return self.readall_nonblock()
+        elif size == 0:
+            data = b''
+        else:
+            data = self.back.stdin.read(size)
+            if(data == b''):
+                raise BrokenPipeError('Tried to read on broken pipe')
         if self.logonread : ilog(data, file=sys.stdout, color=NORMAL)
         self.last = data
         return data